Metal cutting machines typically require a fluid to be used with the metal cutting-tool both as a lubricant and a coolant. During the metal cutting process that fluid accumulates metal cutting or swarf that must be removed from the fluid periodically. In the case of electric discharge machines, and particularly those using wire as a cutting tool, a fluid is used as a dielectric and must be electrically neutral in order for the electric discharge machine to operate properly and accurately. Electric discharge machines typically have a filter reservoir through which the dielectric fluid is filtered. Such filters are usually stationary, open to the air and have metal filter elements. The filters must be cleaned periodically of the swarf accumulated on the filter elements.
One major problem with the current filtering system is that during the filter cleaning procedure the electric discharge machine must be stopped and the cleaning procedure is a time consuming process. The longer the machine is not running, the less productive that machine is for its owner.
Another problem experienced in the industry is that during the procedure of removing the filter element from the open, filter reservoir some of the metal swarf falls off the filter element and back into the dielectric fluid thereby reducing the previous achieved degree of purity of that fluid.
Another problem encountered is that each electric discharge machine has to have a filter reservoir next to the machine. This not only takes up valuable floor space but also limits the ability of the machine operator from maneuvering various related machinery near the electric discharge machine.